Fusible trip mechanism for automatic cutoff valves



May 12, 1953 H. H. SHIELSI 2,638,106

FUSIBLE TRIP, MECHANISM FOR AUTOMATIC CUTOF'F VALVES Filed April 21, 1950 a! as if 72 E I 54 J 6 I I IL 21 t? 33 4 if 75 a j 5 14 1 if 5 3g c Q' g 5 30 r j v my E H 5 /152. .5', 43 Y INVENTOR.

firroewsx preside eludes Patented May 12, 1953 "UNITED STATES PATENT OFFICE FUSIBLE TRY? MECHANISM AUTO VALVES This invention relates to valve mechanism for pipe lines carrying gas, oil, ammonia, steam or at er fluids into building's, under pressure, and has particular reference to emergency closing meansfor such valves.

It lathe general object of the invention to closing means tor such valves which inand is actuated by a collapsible element. it is a iurtherobject of the invention to provide a valveand valve control mechanism both of which are leak-proof not only while the valve tamainam normai open position but also when,

after an emergency has caused it to be closed. it has to be reset for continued operation. A still further obiectis to provide improved means for iacilitatilfig the resetting of such valve mechal' iisml Another abject cf the invention is to provide improved means which is very sensitive to heat to the end that the emergency of the" closing of the valvemay take effect upon relatively small predetermined temperature rise.

Another object is to provide valve closing means which is controllable from points outside f the building within which the valve is placed.

These and other objects of the invent-ion will be better understood from the following detailed description particularlywhen reference is had to the accompanying drawings in which preferred forms of the invention are illustrated. In the drawings:

Fig. 1 is: a cross-sectional view substantially through the vertical center of the device embodying the invention;

my. -2 is asimilar view showing the valve control similar to that of Fig. lbut attfle'hed to a different/"type of valve; and

3 illustrates diagrammatically a modified im m of actuating means for the valve control.

Retell-Irma in the instsmce to Fig. 1, it is noticed that: the numeral I designates a valve having fluid passage 2 therethrough and a: valve seat 3 in. the center of this passage. A

cylindrical bore 4 extends from the top otthe' casvertically downward into this passage in axial with the said valve seat; The upper at; this bore is internally, provided with screw threads 14 of a size to receivethereil'i the threads Mi 3168,11 5 which tightly closes the entrance to this: here: The: cap extends downward a distance below th'a'screw thereof to provide there'- in a; cvlindrioat chamber 6" within which a valve stem? is fitted for axial sliding movement. The stem terminates at the lower endthereof in the valves and. this valve is, by means of a plunger W engaging an annular groove -9' between the 2 stem and the valve head, maintained inthe with drawn position in Fig; is a shrine 5H urges downward movement of the valve stem to close the valve.-

To the side of thecasing l is shown scanned a box shaped frame It, forming a chamber 16- Within which the valve: control mechanism mounted in the f diloiffihg mahriell'.- Into tral portion or this chamber extends" a postl'ch l I of the valve! casing and a cylindricai recess E8. is sunk" into: the inner time (if this casing extension axial alignment with the plunger |0.- latter is shown fitted with ahead [9 (if a siwto slide freely within this bore and a Spring Zfl within the bore urges the plunger away from the valve stem, Such inward movement of the manger is checked by means oi lever connections which for the purpose of illustration are shown to include. an inner lever 25 pivdtally at 28 on a lug: M or. the casing member IT, A Ilmob 22- of this lever" contacts a diaphragm H which tightly closes the entrance to the bare t8 and this kn'db is in axial alignment with the en lar gd central portion 28 of the plunger head- I 9. From this description it is" seen that the spring wards the plunger and the diaphragm 21 knob 22' oi the lever. I

A; second boss- 38 extends inward-1x trout the casing portion I1 to brovide a pivotala snpmtt- 3| which is positioned diametrically ophostta pivot 26. A second lever 32 extends fi'l l'livtm nivot 3| parallel. with the lever 25 and rically in the opposite? direction.v let er M b at the outer end thereof shown fitted with a he 33, which is by means of a: screw 34 seated in end thereof fltte'd to receive a vtusible element 35 A hcss 36 rises from the casing pdrtioh W ahd this bd-s's siniilai ly" fitted to receive the opposite end of the fuse 35 A screw 31 extends the ei-id- (Sf the level? 3 2 ah-d tha 6nd 0!" screw isshown contacting the catch em ottlse inner lever 2'5 comtlotes the central mechanism: ofthe valve.

It sh'ouId clear to anyohe vessed sit that the pressure of the some n pressure of the spring becomes gradually reduced to such an extent that the tension on the fuse element is negligible. It is for this reason possible to make use of an extremely flimsy fuse element which will surely collapse the moment the temperature surrounding the valve reaches a predetermined degree of heat.

While in Fig. 1 is illustrated a conventional type of globe valve'f'or controlling a conduit carrying a gaseous fluid and which is designed quickly to snap into closed position in response to undue rise in temperature, I have found it possible to adapt the same type of valve control mechanism into the peripheral surface of the valve stem.

It is above stated that it is one of the objects of the present invention to provide means for conto the type of valve normally employed to con- 1 trol the flow of liquids, such as oil, through a conduit. This type of mechanism is, in Fig. 2, shown to include a valve casing 40 to the side surface of which a box-shaped frame 4| is secured in the same manner that the frame I5 is mounted in position on the valve casing l and this frame may be identical with the frame l5. The control mechanism within the framing may also remain substantially as above described and it is in like manner fitted with a plunger 42 which 'is placed in position normally to maintain the -valv stem 43 in retracted position. However, the valve is, in this view of the drawing, shown tripped in order better to illustrate the positions taken by the levers 25 and 32 when the temperature rise causes the fuse to melt.

From thevalve 43 rises a threaded shank 44 which, in turn, is held rigidly in position in the screw threads. of a thimble-shaped valve stem '45 and the latter is fitted to slide axially within -the bore 46 of the casing. A spring 4'? urges the valve into the closed position of Fig. 2. It is noticed that the shank 44 is undercut to provide an annular groove 48 of a size to receive the end of the plunger 42 when the valve is raised into open position, as will now be described. A cap 50 "closes the entrance to the casing bore 46 and this cap is axially perforated to receive the reduced portion of a stem 52. as a nut 53 engages the threaded end of the stem 1 to lock it rigidly in position in the cap. This stem extends through and is slidably fitted within Suitable means, such the head 54 of the valve stem. To the lower end of the stem is rigidly secured a cylindrical head 55 forming a piston which is fitted to slide within the cylindrical bore 56 of the valve stem. A portion of this piston is broken away in order to illustrate that it is fitted with a number of perforations 51 The space within the valve stem is filled with a heavy oil, or the like, before the valve is screwed into position therein.

While the valve remains in the closed position of Fig. 2;"1'10 fluid can pass through the conduit 60; nor can any portion of the liquid leak out of the valve casing when the parts are properly proportioned and fitted together. When it is time to reopen the valve, it is merely required to unscrew the cap 50 and to continue the withdrawal movement until the plunger 42 reaches a position of alignment with the annular groove 48. The

frame or cover M has at the same time been removed from the valve case by withdrawal of the fastening screws 5B, 61. If the levers 25, 32, by finger pressure, are lightly urged toward the position shown in Fig. 1, it is found that the plunger 42 will slide into the annular groove 48 the moment it reaches the position of registration therewith. The valve is now held in open position and a new fuse may be applied to lock it permanently in open position. The cap 50 may then be reseated tightly to enclose the valve mechanism.

trolling the valve closing mechanism from points outside of the building within which the valve is placed. Illustrative of such means I have, in Fig. 3, shown the outer levers 32 of Figures 1 and 2 replaced by a lever lit, to the upper end of which a pawl II is pivotally secured. The outer end of this pawl is shaped to engage a boss 12 which takes the place of the boss 36 of the casin mem- -ber 11. Y

magnet thereby to withdraw the pawl and so to release the control mechanism for closing'movement of the valve. geous to provide means, such as a spring 18, more securely to maintain the pawl H in engagement with the boss 12. When the perforation of the pawl, through which the end of the rod 13 ex-- tends, is elongated substantially a indicated at 19, it is found that the lever 10 i afforded more freedom to swing into the valve closing position of Fig. 2.

While I have above described preferred forms of the invention it should be clear to anyone familiar with the art that modifications of proportions and arrangments may be embodied therein Without departing from the spirit of the invention. It is the intention therefore to be limited only as indicated by the scope of the claims hereto appended.

I claim:

1. A valve mechanism comprising, a casing having a valve seat therein, a valve slidable in the casing, resilient means urging said valve toward the said seat, a plunger engaging the valve to maintain it in open position, resilient means urging said plunger away from the valve, a diaphragm abutting the outer end of said plunger and closing an opening of the casing at ,the end of the plunger, diaphragm contacting means including two levers, each pivotally mounted at one end thereof on the casing, one lever having intermediate its ends a knob contacting said diaphragm, the other lever having intermediate its and closing an opening of the casing at the end It may be found advantaof the plunger, a lever pivotally mounted at one end thereof on the casing and contacting the outer surface of the diaphragm, a second lever pivotally mounted at one end thereof on the easing, the pivoted end portion of which contacts the free end of said first named lever, and a fusible element extending from the casing to the free end of said second lever for locking the levers in position to maintain the plunger in engagement with the valve.

3. A valve mechanism comprising, a casing having a valve seat therein, a valve slidable in the casing, resilient means urging said valve toward the said seat, a plunger engaging the valve to maintain it in open position, resilient means urging said plunger away from the valve, a diaphragm abutting the outer end of said plunger and ClOSiIlg an opening of the casin at the end of the plunger, a lever pivotally mounted at one end thereof on the casing and contacting the outer surface of the diaphragm, a second lever pivotally mounted at one end thereof on the easing, an adjustable element at the inner end thereof contacting the free end of said first named lever, and a fusible element extending from the casing to the free end of said second lever for maintaining the plunger in engagement with the valve.

4. A valve mechanism comprising, a casing having a valve seat therein, a valve slidable in the casing, said valve having an annular groove intermediate its ends, resilient means urgin said valve toward said seat, a plunger engaging the groove of the valve to maintain it in open position, resilient means urging said plunger away from said valve, a lever assembly pivotally mounted on the casing and movable to advance said plunger into the said groove, a diaphragm intersecting said plunger and lever assembly and seated in an opening of the casing tightly to close the interior of the casing from the exterior thereof, and a fusible element normally lookingthe lever assembly in position to maintain the plunger advanced.

5. A valve mechanism comprising, a casing having a valve seat therein, a valve slidable in the casing, resilient means urging said valve toward the said seat, a plunger engaging the valve to maintain it in open position, a spring urging said plunger away from the valve, a diaphragm abutting the outer end of said plunger and closing an openingof the casing at the end of the plunger, a lever pivotally mounted at one end thereof on the casing and having intermediate its ends a boss contacting the outer surface of the diaphragm, a second lever pivotally mounted at one end thereof on the casing, an adjustable element in said second lever contacting the free end of said first named lever, a boss on the easing, a clamping screw in said boss, a clamping screw engaging the free end of said second lever, and a fusible element engaged by said clamping screws to lock the levers in position to maintain the plunger advanced.

HERBERT H. SHIELS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 59,764 Farrar Nov. 20, 1866 1,056,009 Crouch Mar. 18, 1913 1,140,313 Paine May 18, 1915 1,609,930 Cohen Dec. 7, 1926 1,897,076 Shand Feb. 14, 1933 2,020,558 Lovekin Nov. 12, 1935 2,181,523 Shiels Nov. 28, 1939 2,282,244 Ransome May 5, 1942 

